Monkeypox and smallpox are viral infections caused by monkeypox virus and smallpox virus infections respectively. They differ in symptoms and severity. 1. Symptoms: Monkeypox causes a rash one to three days after the onset of fever, and the rash is mainly concentrated on the patient’s face and limbs. Smallpox usually causes a rash two to three days before the onset of fever, and the rash will gradually spread from the face to the trunk. 2. Different severity: smallpox is more serious than monkeypox, which usually causes fever, headache, rash and other symptoms, while smallpox, in addition to similar symptoms, can also be bacterial infection of organs, sepsis, keratitis and other symptoms. The symptoms can be more severe compared to monkeypox. Monkeypox and smallpox differ in terms of symptoms and severity, and it is recommended that the diagnosis be made under the guidance of a doctor.